Diffuse optical tomography using near-infrared light with sufficient safety and high permeability for living organisms is known as a method for obtaining tomographic information of living organisms. Since the near-infrared light used in this diffuse optical tomography, unlike X-rays, has very low invasiveness for living organisms and shows significantly different spectral characteristics in the frequency band of near-infrared light depending upon materials in the organisms, there are advantages including one such that various pieces of metabolic information of biological matter such as oxygen can be collected in high temporal resolution. A measuring device using this diffuse optical tomography is compact and inexpensive per se and is less stressful for a person as measuring subject; e.g., there is no need for the measuring subject to maintain a posture during measurement. Therefore, various studies have been conducted with expectations of application to more detailed analyses of vital functions and research is under way on an analysis method and others for obtaining tomographic information of living organism from the result obtained by irradiating a measuring object with near-infrared light (e.g., cf. Patent Literature 1).